CVE-2021-3735 Denial of service in QEMU

What is CVE-2021-3735?

CVE-2021-3735 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 26 Aug 2022. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A deadlock issue was found in the AHCI controller device of QEMU. It occurs on a software reset (ahci_reset_port) while handling a host-to-device Register FIS (Frame Information Structure) packet from the guest. A privileged user inside the guest could use this flaw to hang the QEMU process on the host, resulting in a denial of service condition. The highest threat from this vulnerability is to system availability.

Weakness: CWE-400, CWE-667

Which versions are affected by CVE-2021-3735?

It affects 2 products.

Products include Debian Debian Linux, Qemu Qemu.

How do I fix CVE-2021-3735?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-3735 being exploited?

There is no known exploitation of CVE-2021-3735 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2021-3735, DEBIAN-CVE-2021-3735, ECHO-8c6a-e78a-b98a, GHSA-ch7h-w2mm-gm7m, UBUNTU-CVE-2021-3735.